1. Field of the Invention
The present invention relates to a fluid delivery adapter unit for an endoscope that is used as an auxiliary fluid delivery unit for selectively interfacing fluid supply equipments with an endoscope to deliver and spray fluid through a distal end of a flexible insertion tube of the endoscope.
2. Description of Related Art
Typically, an endoscope is provided with a plurality of fluid delivery and suction means for delivering and sucking fluid. One of such fluid delivery and suction means is a body-fluid suction device including a suction tube that is detachably connected to a working channel of the endoscope through which a medical instrument such as a biopsy sampling device, catheter, etc. and a vacuum pump connected to the suction tube. Suction of a body fluid is performed by operating a suction valve installed to an operating headpiece of the endoscope. In the event where it is required to clean a viewing window at a distal end of an insertion tube of the endoscope, a cleaning fluid delivery means is used to deliver a cleaning liquid to the distal end of the insertion tube. The cleaning fluid generally consists of a cleaning liquid such as water and pressurized air. Cleaning of a disfeature viewing window is performed by spraying a cleaning liquid onto the viewing window to wash away crud and/or grime and then delivering pressurized air to blow off drops of liquid from the viewing window.
As just described, endoscopes are typically provided with a liquid delivery passage and an air delivery passage. Delivery of liquid and air are selectively started by manipulation of a liquid/air delivery valve installed to the operating headpiece. In many instances, these liquid delivery passage and air delivery passage are merged together into one outlet port at their distal ends so that the outlet port is connected to a spray nozzle oriented toward the viewing window at a distal end of the insertion tube. In such an instance, cleaning of the viewing window is performed by operating the liquid/air delivery valve to cause deliver and spray of a cleaning liquid through the spray nozzle in the first place and then switching the liquid/air delivery valve to cause deliver and spray of pressurized air through the spray nozzle in the second place. In this manner, cleaning of the disfeatured viewing window of the endoscope is performed while the insertion tube remains left within a body cavity of a patient.
A certain type of endoscope is provided with fluid delivery means for spraying high pressure water against a wall surface of a body cavity of a patient so as thereby to remove away crud adhered to the wall surface of the body cavity or to disperse a dye solution toward the wall surface of the body cavity. This type of fluid delivery means causes a jet stream of desired liquid through an injection nozzle at a distal end of the insertion tube of the endocope. In this instance, it is different from the fluid delivery means for cleaning a viewing window that sprays a cleaning liquid toward the viewing window in that the liquid is sprayed in a direction of the field of view through the injection nozzle.
The fluid delivery means has a fluid outlet port at a distal end of the insertion tube and a fluid inlet port that is located on the operating headpiece. A large variety of locations of the fluid inlet port are possible. In the case where the fluid inlet port is located at an end of the operating headpiece opposite to an end from which the insertion tube extends, the fluid delivery passage extends approximately straight between the fluid inlet port to the fluid outlet port. This is advantageous from the viewpoint of cleaning the interior of the fluid delivery passage. In order to supply a high pressure fluid, a fluid supply equipment is connected to the endoscope through the fluid inlet port-that generally comprises a fluid tank, a fluid conveyance tube and a fluid supply pump.
In the meanwhile, endoscopes are provided with a universal tube or sheath extending from an operating headpiece which encloses light guide means for guiding light for illuminating a body cavity from a light source provided separately from the endoscope and, in the case of electronic endoscope, a video signal transmission cable for transmitting video signals from a CCD image pick-up device at a distal end of an insertion tube of the endoscope to a vide monitor provided separately from the endoscope. In the case where an endoscope is connected with the fluid conveyance tube in addition to the universal tube at the operating headpiece, the fluid conveyance tube possibly gets in operator's hair when the operator manipulates the endoscope taking a grip on the operating headpiece. Furthermore, there is fear that the fluid conveyance tube is broken near the fluid inlet port and, in that event, blocks desirable delivery of fluid. For these reason, it may be desirable to use a generally L-shaped plumbing connector pipe to connect a fluid conveyance tube to the fluid inlet port so that fluid conveyance tube extends in the approximately same direction as the universal tube, as described more fully, for example, in Japanese Unexamined Patent Publication No. 2001-292963.
Fluid supply equipments for use with the endoscope include manual type fluid supply equipments such as a syringe that is manipulated by a surgical practitioner apart from the pumping type fluid supply equipment. Manual fluid supply using a syringe capacitates a surgical practitioner to perform unrestrained quantity and/or pressure control of fluid delivery and is often preferred depending on the end of fuel delivery. However, the prior art fuel delivery system has a problem with connectivity of the plumbing connector pipe with a syringe or operationality of a syringe connected to the plumbing connector pipe resulting from directional consistency between the plumbing connector pipe and the universal tube. In particular, since the plumbing connector pipe faces downward when taking a single-handed grip on the operating headpiece of the endoscope, manipulation of the syringe with the other hand is inevitably accompanied by awkward motion with the consequence that it is hard for the surgical practitioner to impart injection force to the syringe.